Currently, in the case of a health problem a patient goes to the medical specialist where the patient undergoes a series of tests in order to formulate a diagnosis, based on which a treatment can be prescribed. Often the patient has to go through several visits to different specialists and then to the place where the treatment could be delivered. Acquiring eyewear to correct the problem of vision loss is an example of the current standard health care practice. Although such practice provides a high quality solution for the common health care problems, it has several limitations and shortcomings. Among them are cost, duration of time before the problem is detected and corrected, and inapplicability for the counties where the health care systems are not well established and operated, and are lacking well-trained specialists. The latter is especially obvious in developing nations where the shortage of health care specialists, funding, and equipment results in serious problems for the population's health. To overcome those shortcomings systems are being developed that can perform several steps related to testing or diagnostics in an automatic fashion. In the area of optometry, for example, there exist several devices that perform automatic measurement of the refractive errors. These devices are known as Autorefractometers. For example, the Auto Refractometer Model KA-1000, manufactured by Kowa Optimed Inc., Torrance, Calif., which is an ophthalmic products division of Kowa Company, Japan, is used to automatically specify a corrective prescription of glasses or contact lenses for a user. Another device, Luneau L62-3D, manufactured by LUNEAU S.A., France, in addition to measuring refractive errors of the lens, provides an estimation of the optical properties and topography of cornea, which is particularly useful for a proper contact lens prescription. The systems, which perform higher order aberration measurements employing a wave front sensor, are currently being sold and further developed. Such a device is being developed by Ophthonix, Inc., San Diego, Calif. The Ophthonix device is described in U.S. Pat. No. 6,761,454 and it shines light into the eye and measures changes in the wave properties of the light reflected back by the retina. From these changes, the apparatus can calculate the measurements on any existing irregularities of the eye lens.
Automatic measurement of refractive errors or higher order aberrations enables performance of necessary diagnostics of the person's vision in terms of the prescription lenses. Devices of this type can be operated by an assistant who requires only a limited training or by the user. However, such devices are not capable of automatically producing corrective eyewear, which is a highly desirable attribute for countries line China and India, where a large percentage of the population with the near- or far-sightedness lacks an access to the prescription eyewear.
In order to provide prescription eye-ware, presently an optometrist or an eye professional performs a variety of measurements including bridge size, inter-pupillary distance, temple length, eye size and visual axis measurements, in addition to the measurements of refractive errors and/or higher order aberrations, which could be done automatically as described above. Usually, the optometrist performs a process of fitting the eyewear to the person's head, which may be time consuming. This operation is done to properly adjust the frame to the person's facial structure.
U.S. Pat. No. 6,682,195 discloses a method of measuring parameters required for fitting of an eyeglasses frame using digital cameras. Examination of the eye is not only used for prescribing corrective eyewear, but can be also used for screening and diagnosing a variety of ophthalmologic diseases, such as cataract, uveitis, glaucoma, macula degeneration, visual field changes and others.
High resolution longitudinal and depth imaging can be performed by optical coherence tomography (OCT) as described in articles “Optical Coherence Tomography” by D. Huang et al., Science 254, (1991), pp. 1178-1181; and “Optical Coherence Tomography” by A. F. Fercher, in Journal of Biomedical Optics Vol. 1, No. 2, April 1996, pp. 157-173. An OCT based instrument called StratusOCT is now commercially available from Carl Zeiss Meditec, Jena, Germany which produces OCT cross sectional images of the retina for objective measurement and clinical evaluation for the detection of glaucoma and retinal diseases. Examples of OCT apparatus for longitudinal and transverse imaging are described in U.S. Pat. Nos. 5,493,109; 5,537,162; 5,491,524; 5,469,261; 5,321,501; and 5,459,570. Another example, U.S. Pat. No. 6,293,674 discloses the use of optical coherence tomography (OCT) system for diagnosing glaucoma while examining the eye. This patent describes an apparatus that images the patient's retina to determine the parameters of the retinal nerve fiber layer, such as thickness, relevant to glaucoma.
It is also known that eye exams may lead to detecting other illnesses. Alzheimer's disease, mental disorders, diabetes, cancer and drug usage were found to generate changes in the eye and eye behavior. For example, in the U.S. Patent Application Publication Ser. No. 2002/0182152 A1 described a method of diagnosing Alzheimer's disease by applying a dynamic light scattering probe to the eye lens of the mammals. In research studies it was found that the beta amyloid proteins that form plague in the brain in Alzheimer's patients tend to aggregate in the eye lens which increases the light scattering characteristics of the lens and can be therefore detected at the early stage of the illness.
U.S. Pat. No. 6,704,588 discloses a method and an apparatus for non-invasive determination of blood glucose levels by performing measurements in the eye using light polarization effects.
The above systems provide measurements related to the condition of the eye with respect to a number of illnesses and health status but do not provide any automated means of fulfillment.
There is therefore a need for systems that will provide automated diagnosis of medical conditions, related to vision, ophthalmologic diseases as well as other types of health conditions, and that will automatically provide the necessary fulfillment of the patient's needs as dictated by the automated diagnosis. The present invention satisfies this need.
The foregoing and other objects, features, and advantages of the invention will be apparent from the following more particular description of the preferred embodiments of the invention, as illustrated in the accompanying drawings.